Street art is visual art created in public locations, usually unsanctioned artwork executed outside of the context of traditional art venues. Other terms for this type of art include "independent public art", "post-graffiti", and "neo-graffiti", and is closely related with urban art and guerrilla art. Common forms and media include spray paint graffiti, stencil graffiti, wheatpasted poster art, sticker art, street installations, and sculpture. Video projection and yarn bombing have also gained some popularity near the turn of the 21st century.